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Previewing distractors facilitates efficient detection of a target appearing subsequently with any remaining distractors. Visual marking, specifically, top-down inhibition of old items, is induced by the inhibitory template that forms while previewing old items, and continues to be maintained during the target search. Extant studies have examined inhibitory template characteristics using additional tasks or events. In the present study, an endogenous cueing paradigm was combined to examine the interaction between spatial facilitation of cueing and the ability to inhibit old items. An endogenous cue was presented during the preview period, resulting in competition between two top-down controls, endogenous orienting and the inhibitory template; endogenous spatial cueing and visual marking effects did not simply function concurrently. Rather, either of them could be effective alternately for one trial. These findings suggest that the inhibitory template cannot function concurrently with another top-down control for visual search, though it is not damaged. [ABSTRACT FROM AUTHOR]

Although visual search studies have primarily focused on search behavior, concealment behavior is also important in the real world. However, previous studies in this regard are limited in that their findings about search and concealment strategies are restricted to the spatial (two-dimensional) domain. Thus, this study evaluated strategies during three-dimensional and temporal (i.e., spatiotemporal) search and concealment to determine whether participants would indicate where they would hide or find a target in a temporal sequence of items. The items were stacked in an upward (Experiments 1–3) or downward (Experiment 4) direction and three factors were manipulated: scenario (hide vs. seek), partner type (friend vs. foe), and oddball (unique item in the sequence; present vs. absent). Participants in both the hide and seek scenarios frequently selected the oddball for friends but not foes, which suggests that they applied common strategies because the oddball automatically attracts attention and can be readily discovered by friends. Additionally, a principle unique to the spatiotemporal domain was revealed, i.e., when the oddball was absent, participants in both scenarios frequently selected the topmost item of the stacked layer for friends, regardless of temporal order, whereas they selected the first item in the sequence for foes, regardless of the stacked direction. These principles were not affected by visual masking or number of items in the sequence. Taken together, these results suggest that finding and hiding positions in the spatiotemporal domain rely on the presence of salient items and physical accessibility or temporal remoteness, according to partner type. [ABSTRACT FROM AUTHOR]

In the process of searching for targets, our visual system not only prioritizes target-relevant features, but can also suppress nontarget-related features. Although this template for rejection has been well demonstrated, whether the features (i.e. the objects) or locations are suppressed remains unresolved due to the experimental paradigms in previous studies: in particular, object-based templates for rejection were confounded with location-based inhibition in visual search paradigms. The present study examined an object-based template for rejection by introducing search arrays comprised of two overlapping shapes with search items distributed along the shape's contours. To discourage location-based inhibition, the two shapes were spatially intermingled (Experiment 1), rotated (Experiment 2), or jiggled (Experiment 3). Participants identified the colour of a target cross. The pre-cue indicated the shape in which the target would appear (positive cue condition), the shape in which only distractors would appear (negative cue condition), or the shape that was irrelevant to the current search array (neutral cue condition). In all three experiments, the reaction times for the negative cue condition were shorter than those for the neutral cue condition, which is a hallmark of the object-based template for rejection effect, even under conditions in which location-based inhibition was discouraged. [ABSTRACT FROM AUTHOR]

Recent studies suggest that the 'mere presence' of a mobile phone impairs social interactions and neuropsychological test performance. The present study examined whether the presence of a mobile phone causes spatial bias toward the device during a visual search task. Participants identified a target among spatially distributed non-targets. We manipulated three factors: device presence (mobile phone or notepad), target congruency (congruent or incongruent), and attentional load (set size 8 or 24). A mobile phone (or a notepad in the control condition) was placed on the left side of the computer screen. Participants also completed a questionnaire to measure Internet usage and attachment. Participants with high scores on the questionnaire rapidly identified the target at the congruent (same side as the phone) location, but the mere presence effect did not occur in this condition. In contrast, participants with low scores on the questionnaire demonstrated the mere presence effect, but no spatial bias was observed. These results suggest that the mere presence effect can be modulated by individual differences in the degree to which a device is appealing. [ABSTRACT FROM AUTHOR]

The present study examined whether attention can be flexibly controlled to monitor two different feature dimensions (shape and color) in a temporal search task. Specifically, we investigated the occurrence of contingent attentional capture (i.e., interference from task-relevant distractors) and resulting set reconfiguration (i.e., enhancement of single task-relevant set). If observers can restrict searches to a specific value for each relevant feature dimension independently, the capture and reconfiguration effect should only occur when the single relevant distractor in each dimension appears. Participants identified a target letter surrounded by a non-green square or a non-square green frame. The results revealed contingent attentional capture, as target identification accuracy was lower when the distractor contained a target-defining feature than when it contained a nontarget feature. Resulting set reconfiguration was also obtained in that accuracy was superior when the current target's feature (e.g., shape) corresponded to the defining feature of the present distractor (shape) than when the current target's feature did not match the distractor's feature (color). This enhancement was not due to perceptual priming. The present study demonstrated that the principles of contingent attentional capture and resulting set reconfiguration held even when multiple target feature dimensions were monitored. [ABSTRACT FROM AUTHOR]

The present study investigated whether faces capture attention regardless of attentional set. The presentation of a face as a distractor during a visual search has been shown to impair performance relative to when the face was absent, implying that faces automatically attract attention. If attentional control is contingent on the observer's current goal, faces should not capture attention when they are irrelevant to the observer's attentional set. Previous studies demonstrating face-induced attentional capture used faces that were relevant to the task. Thus, a task in which faces were completely irrelevant to the observer's set was created. Participants identified a target letter among heterogeneously colored non-targets while ignoring a peripheral facial image that appeared as a brief distractor. No face-specific capture was observed when the target-distractor stimulus onset asynchrony (SOA) was long (Experiment 1). When the SOA was shortened, attentional capture by irrelevant faces was observed (Experiment 2). Experiment 3 extended this finding to all conditions, regardless of the attractiveness of faces. No such capture effect was found in Experiment 4 with inverted-face distractors. These results indicate that completely task-irrelevant faces break through top-down attentional set given a brief distractor-target SOA. [ABSTRACT FROM AUTHOR]

Selective attention plays an important role in identifying transient objects in a complex visual scene. Attentional control ability varies with observers. However, it is unclear what neural mechanisms are responsible for individual differences in attentional control ability. The present study used the following attentional blink paradigm: when two targets are to be identified in rapid serial visual presentation, the processing of the first target interrupts the identification of the second one appearing within 500 ms after the first-target onset. It has been assumed that the reduction of the second-target accuracy is mainly due to a transient inhibition of attentional reorienting from the first to the second target, which is modulated by the GABA system. Using magnetic resonance spectroscopy, we investigated whether individual variation of attentional blink magnitude is associated with GABA concentrations in the left prefrontal cortex (PFC), right posterior-parietal cortex (PPC), and visual cortex (V C) of humans. GABA concentrations in the PFC were related negatively to attentional blink magnitude and positively to the first-target accuracy. GABA concentrations in the PPC were positively correlated with attentional blink magnitude. However, GABA concentrations in the VC did not contribute to attentional blink magnitude and first-target accuracy. Our results suggest that frontoparietal inhibitory mechanisms are closely linked with individual differences in attentional processing and that functional roles of the GABAergic system in selective attention differ between the PFC and PPC. [ABSTRACT FROM AUTHOR]

We investigated whether attentional set is available at the beginning of a trial or whether it develops gradually within a trial. Thus, we manipulated the time from the onset of a trial to a target and observers' search strategy. We also observed the effect of the presence or absence of distractors as an index of the temporal development of attentional set. Participants identified a target letter embedded in a stream of rapidly presented nontargets while ignoring peripheral distractors. Baseline accuracy when no peripheral distractor was presented increased as the target appeared later in the stream, suggesting attentional awakening. Identification accuracy was impaired by the presence of peripheral distractors (i.e., attentional capture) early in the stream only when observers adopted the feature search mode. The magnitude of attentional capture increased over the course of the first 1,000 ms of a trial under the singleton detection and feature search modes. These results suggest that singleton detection mode requires time for a bottom-up signal to be effective in capturing attention, whereas the feature search mode does not require such a warm-up period to be effective and is available from the beginning of viewing the stream. [ABSTRACT FROM AUTHOR]